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排序方式: 共有1733条查询结果,搜索用时 31 毫秒
61.
Inta Zepa Kirsti Hurmerinta Outi Kovero Maunu Nissinen Mauno Könönen Jan Huggare 《Acta odontologica Scandinavica》2013,71(6):237-242
The aim of the present study was to investigate associations between thoracic hyper- and hypokyphosis, head posture, and craniofacial morphology in young adults. Using forward bending test and spinal pantographic measurements, 31 subjects, 16 with thoracic hyper- and 15 with hypokyphosis, were selected from a population-based cohort of 430 young adults. Lateral roentgen-cephalograms were taken in natural head posture and craniofacial and postural angular measurements were calculated. Any statistically significant differences between the groups - thoracic hyperkyphosis and thoracic hypokyphosis - were analysed using Student's t test. Subjects with thoracic hyperkyphosis had a larger atlantocervical angle (At/CVT, P < 0.01) than subjects with thoracic hypokyphosis. However, head position (NSL/VER)was similar in both groups, probably owing to the visual perception control of craniovertical relation. There was no statistically significant difference in craniofacial morphology between the groups. 相似文献
62.
背景:关节镜下重建交叉韧带已得到广泛应用,关于腱骨愈合状态的研究多集中在患肢功能恢复以及愈合程度及稳定性观察方面。目的:了解韧带重建过程中各种固定方式对肌腱.骨界面愈合的影响。方法:2009年7月至2009年9月以长白二号体重100千克左右的八头成年猪的双膝关节作为实验对象进行动物实验,采用四种固定方式对腱-骨进行固定,包括纽扣接骨板悬吊固定、肌腱包裹自体松质骨方式、界面挤压螺钉固定、横穿可吸收钉固定,对手术后6周、12周时界面愈合的情况进行病理切片观察。结果:纽扣接骨板固定模式腱骨界面愈合均匀,理论抗拉力大,相反固定物对腱骨界面干扰明显的界面愈合不理想,骨纤维细胞排列不整齐,理论拉力降低,尤其表现在界面挤压螺钉方面;对于有自体松质骨植入的在腱骨愈合过程中活性骨质坏死,无促进腱骨愈合的作用。结论:在腱骨愈合过程中界面固定方式对早期愈合有不同程度的影响,悬吊固定方式腱.骨愈合界面形态学表现理想。 相似文献
63.
Brian D. Mills Janie Lai Timothy T. Brown Matthew Erhart Eric Halgren Judy Reilly Anders Dale Mark Appelbaum Pamela Moses 《Neuropsychologia》2013
This study investigated the relationship between white matter microstructure and the development of morphosyntax in a spoken narrative in typically developing children (TD) and in children with high functioning autism (HFA). Autism is characterized by language and communication impairments, yet the relationship between morphosyntactic development in spontaneous discourse contexts and neural development is not well understood in either this population or typical development. Diffusion tensor imaging (DTI) was used to assess multiple parameters of diffusivity as indicators of white matter tract integrity in language-related tracts in children between 6 and 13 years of age. Children were asked to spontaneously tell a story about at time when someone made them sad, mad, or angry. The story was evaluated for morphological accuracy and syntactic complexity. Analysis of the relationship between white matter microstructure and language performance in TD children showed that diffusivity correlated with morphosyntax production in the superior longitudinal fasciculus (SLF), a fiber tract traditionally associated with language. At the anatomical level, the HFA group showed abnormal diffusivity in the right inferior longitudinal fasciculus (ILF) relative to the TD group. Within the HFA group, children with greater white matter integrity in the right ILF displayed greater morphological accuracy during their spoken narrative. Overall, the current study shows an association between white matter structure in a traditional language pathway and narrative performance in TD children. In the autism group, associations were only found in the ILF, suggesting that during real world language use, children with HFA rely less on typical pathways and more on alternative ventral pathways that possibly mediate visual elements of language. 相似文献
64.
Eyal Zvi Shamir Stanley Morris Cassan Anat Levy Tova Lifshitz Ricardo Tarrasch 《Psychiatry research》2013
Since abnormalities in distal upper limb development are among the minor physical anomalies associated with schizophrenia we attempted to determine whether patients with schizophrenia can be identified on the basis of specific morphologic and dermatoglyphic features of the hand. Photographs and prints of the hands of 38 patients with schizophrenia and those of 42 control subjects were evaluated and graded on 13 biometric parameters. Results were statistically evaluated. A combination of three of the parameters was found to have good predicting abilities to distinguish between schizophrenics and controls. Subjects having high values in these three parameters were found to have a higher propensity to be defined as schizophrenics. In order to define a simple rule for classifying subjects we chose a criterion of having a value of 3 (in a scale from 1 to 3) in at least one of these three discriminating variables. This rule yielded an overall accuracy of 81.2%. Among controls, 85.7% of subjects did not fulfill such criteria, while 14.3% were defined as false positives. Among schizophrenics 76.3% achieved this condition while 23.7% were false negatives. The technique's objectivity and ease of application could facilitate the diagnosis of this disease. 相似文献
65.
C. R. Marshall 《Clinical linguistics & phonetics》2013,27(2):71-91
Although it is well‐established that children with Specific Language Impairment characteristically optionally inflect forms that require tense and agreement marking, their abilities with regards to derivational suffixation are less well understood. In this paper we provide evidence from children with Grammatical‐Specific Language Impairment (G‐SLI) that derivational suffixes, unlike tense and agreement suffixes, are not omitted in elicitation tasks. We investigate two types of derivation – comparative/superlative formation and adjective‐from‐noun formation – and reveal that G‐SLI children supply these suffixes at high rates, equivalent to their language matched peers. Moreover, increasing the phonological or morphological complexity of the stimulus does not trigger suffix omission, although it results in non‐target forms that are not characteristic of typically developing children. We discuss what these results reveal about the nature of the deficit in G‐SLI within the context of three hypotheses of SLI: the Extended Optional Infinitive, Implicit Rule and Computational Grammatical Complexity Hypotheses. 相似文献
66.
目的初步探讨消幻汤含药血清对人神经母细胞瘤细胞SH—SYSY的增殖及形态的影响。方法通过连续7d给家兔灌胃给药,制备消幻汤含药兔血清、利培酮含药免血清及空白兔血清。将上述血清作用于SH—sY5Y细胞24~72h,通过倒置显微镜观察舍药血清干预48h的SH—SY5Y细胞的形态,并且每24小时采用MTT法检测SH~SY5Y细胞的增殖情况。结果消幻汤含药血清处理48h的SH—SY5Y细胞突起较长,细胞间接触紧密,并且伸出伪足,虽表现为增殖旺盛,但消幻汤含药血清对SH—SY5Y细胞的增殖与空白血清相比,差异无统计学意义(P〉0.05),而利培酮含药血清则可显著增加sH—SY5Y的细胞数量,呈现对数增殖趋势,与其他各组比较,差异有统计学意义(P〈0.05)。结论消幻汤含药血清对SH—SY5Y细胞的正常形态有促进作用,而对SH—SY5Y细胞的正常增殖无显著干预作用,与利培酮舍药血清作用不同。 相似文献
67.
目的分析安全置入胸椎椎弓根钉相关的椎弓根解剖形态特点,研究在探设成人胸椎椎弓根钉通道过程中需要重点探查的区域。方法使用CT三维重建图像对60位正常发育的成人胸椎椎体和15例胸椎椎弓根钉穿出椎弓根内侧壁的胸椎手术患者进行测量。测量参数包括:临界距离,安全距离,椎弓根钉通道长度,椎弓根宽度,椎弓根横向角,穿出距离。危险区域定义为安全距离和临界距离之差。结果成人不同节段胸椎的临界距离为8.69~10.53 mm,安全距离为14.53~16.16 mm,危险区域为5.10~6.41 mm。临界距离、安全距离与危险区域相对恒定。椎弓根钉通道长度为31.21~45.01 mm,椎弓根宽度为4.03~8.29 mm。椎弓根横向角从T1的27.68°逐渐减少到T12的7.82°。15枚穿出椎板腹侧皮质或者椎弓根内侧皮质的椎弓根钉的穿出距离为(12.68±1.12)mm,所有的穿出距离均介于临界距离和安全距离之间。结论正确认识成人胸椎的临界距离、安全距离和危险区域有助于安全置入胸椎椎弓根钉。 相似文献
68.
The role of semantics in the segmentation of morphologically complex words was examined using event-related potentials (ERPs) recorded to target words primed by semantically transparent (hunter-hunt,) opaque (corner-corn), and orthographically related (scandal-scan) masked primes. Behavioral data showed that only transparent items gave rise to priming. The ERP data showed both N250 and the N400 effects with transparent items generating greater priming than orthographic or opaque. Furthermore, priming effects across conditions revealed the existence of a significant linear trend, with transparent items showing the greatest effects and orthographic items the smallest, suggesting that these priming effects vary as a function of morphological structure and semantic transparency. The results are discussed in terms of a model of morphological processing. 相似文献
69.
We describe 3 unusual B-cell non-Hodgkin's lymphomas in which the entire tumors histologically mimicked marginal zone B-cell lymphoma. All patients were male (mean age, 65 years). Excisional biopsy from lymph node (2 of 3) and parotid gland (1 of 3) showed proliferation of monocytoid B-cells with plasmacytoid features (2 of 3) and conspicuous absence of large lymphoma cells (3 of 3). By immunohistochemistry, cyclin D1 was positive (3 of 3), CD23 was negative (3 of 3), and aberrant expression of CD5/CD43 was present in 1 case. Ki67 labeling was greater than 50% in 1 case and 10% to 25% in the other 2 cases. Evidence of the t(11;14) was detectable in all by molecular techniques. One patient died within 15 months, and the other 2 patients had widely disseminated diseases at the last follow-up (8 months). Based on these features, we believed that the best classification for these lesions is the marginal zone B-cell lymphoma-like mantle cell lymphoma. 相似文献
70.
Minh-Quan Le Fabien Violet Cédric Paniagua Xavier Garric Marie-Claire Venier-Julienne 《International journal of pharmaceutics》2018,535(1-2):428-437
Here, we aimed to develop protein loaded microspheres (MSs) using penta-block PLGA-based copolymers to obtain sustained and complete protein release. We varied MS morphology and studied the control of protein release. Lysozyme was used as a model protein and MSs were prepared using the solid-in-oil-in-water emulsion solvent extraction method. We synthesized and studied various penta-block PLGA-based copolymers. Copolymer characteristics (LA/GA ratio and molecular weight of PLGA blocks) influenced MS morphology. MS porosity was influenced by process parameters (such as solvent type, polymer concentration, emulsifying speed), whereas the aqueous volume for extraction and stabilizer did not have a significant effect. MSs of the same size, but different morphologies, exhibited different protein release behavior, with porous structures being essential for the continuous and complete release of encapsulated protein. These findings suggest strategies to engineer the morphology of MSs produced from PLGA-based multi-block copolymers to achieve appropriate release rates for a protein delivery system. 相似文献